Washing and high pressure jet cleaning apparatus

ABSTRACT

In a washing apparatus for alternately effecting washing at low pressure and high pressure jet cleaning and having a jet nozzle and an injector for supply of a washing agent to the washing fluid during the washing periods, a first conduit by-passing the injector and provided with means adapted to control the passage through said by-pass conduit in response to variations in the pressure downstream of said injector. Said downstream pressure being variable by means of manually operable valve means fitted close by the jet nozzle of the apparatus.

Unite States Patent 1191 1111 3,829,024 Heden Aug. 13, 1974 WASHING AND HIGH PRESSURE JET 3,181,797 5/1965 l-layes 239/317 QLEANING APPARATUS 3,613,997 10/1971 Thompson 239/318 X [75] Inventor: Olle Heden, Alingsas, Sweden FOREIGN PATENTS OR APPLICATIONS ssigneez Euroclean AB, Alingsas, Amal, Italy Sweden 4 Primary ExammerLloyd L. Kmg

[22] F 11695 Sept- 4, 1973 Assistant ExaminerAndres Kashnikow 2 APPL 393 7 Attorney, Agent, or FirmBrumbaugh, Graves,

Donohue & Raymond [30] Forelgn Application Priority Data [57] ABSTRACT Sept. 8, 1972 Sweden 11574/72 In a washlng apparatus for alternately effecting wash- 52 US. Cl 239/310 134/100 137/110 ing at low 10mgre and high Pressure cleaning and 239/443 having a jet nozzle and an injector for supply of a [51] Int Cl Bosh 7 /26 washing agent to the washing fluid during the washing [58] Field 318 340 periods, a first conduit by-passing the injector and provided means adapted to COl'ltI'Ol the passage 3 through said by-pass conduit in response to variations in the pressure downstream of said injector. Said [56] References Chad downstream pressure being variable by means of manually operable valve means fitted close by the jet noz- UNlTED STATES PATENTS 21 e of the apparatus 2,699,731 1/1955 Pollock et al 239/318 X 2,757,047 7/1956 Friedmann 239/310 x 4 C aims, 2 Drawing Figures WASHING AND HIGH PRESSURE JET CLEANING APPARATUS BACKGROUND OF THE INVENTION The present invention refers to a washing apparatus of the kind including a jet nozzle and an injector for supply of a washing agent into the apparatus.

At known apparatuses of this kind the washing agents have been supplied at the suction side of the pump, which means that the pump must be made of a material which is resistant to chemicals. The operation of such apparatuses is complicated as the shiftover from washing at a lower pressure to jet cleaning at a higher pressure must be performed at the pump, which often is located quite a distance away from the working spot.

A carefully adjusted supply of the washing agent is possible only if the fluid capacity of the injector device is about the same during washing at low pressure as during jet cleaning at high pressure. This pressure variation is brought about by using, during jet cleaning at high pressure, a jet nozzle having a small'flow area, and during washing at low pressure, a jet nozzle having a large area, the flow of fluid being kept substantially constant by means of a constant displacement pump. It should be observed that the injector device presupposes a certain pressure variation at its downstream side in order to work.

The drawback with an apparatus of this known type is that the total amount of fluid consumed during washing is high, which means that a part of the washing fluid just flows away without adding to the washing effect, and that the consumption of washing agents is correspondingly high. It is furthermore difficult to use the known injector device in a plant where a common pump is serving a number of independently operable apparatuses and finally a jet nozzle having one big area passage for washing and another smaller area passage for jet cleaning is heavy and difficult to handle.

SUMMARY OF THE INVENTION The purpose of the present invention is to provide an apparatus by means of which it is possible to effect, at

the downstream side of the injector the pressure reducv tion necessary for obtaining the supply of the washing agent independently of the capacity of the pump ahead of the injector and without the necessity'of changing the opening of the jet nozzle. According to the invention this is obtained by a first conduit by-passing the said injector, a first valve means fitted in said by-pass conduit a hydraulically operated governing means adapted to control the position ofsaid first valve means, means fitted adjacent to said governing means and biasing the said first valve means towards closed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows in a schematic view an embodiment of the washing and high pressure jet cleaning apparatus of the invention.

FIG. 2 shows a modified embodiment of the valve means included in the apparatus and fitted downstream of the injector.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, 1 denotes a high pressure pump, which via a conduit 2 is connected to a source of water supply. A further conduit 3 connects the pressure side of the pump to an injector 4. The suction pipe 5 of the injector is provided with a non-return valve 6 which blocks the pipe as soon as the sub-pressure caused by the injector should cease. The suction pipe 5 leads to a container 7 for the washing agent. A by-pass conduit 8, 9

is arranged over the injector 4 and is provided-with a governing valve device generally denoted 10. This valve device includes a first valve member 11 which is biased towards closed position by a spring 14 and operable against the action thereof by a piston 12 working in a hydraulic cylinder 13. To the end of the cylinder working chamber remote from the spring there is connected a conduit 15, the opposite end of which is connected to one branch 9 of the by-pass conduit. The conduit leading away from the injector is denoted 16 and thereto is fitted a pliable hose 17 equipped with a valve means 18, which is provided close by a jet pipe 20 having a nozzle 23. The valve means 18 in this embodiment includes a closure valve 19 and fitted between this and the jet pipe 20 a bleed-off valve 21 by means of which fluid can be discharged during a short period of time in order to bring about a reduction of the pressure downstream of the injector. The bleed-off valve is preferably provided with a check valve 22, which opens at a pressure just below the pressure prevailing in the system.

The apparatus according to the invention operates in the following manner. The pump 1 delivers to the injector 4 a fluid at high pressure, eg 50 atmospheres and at a flow rate of l2 liters/min. When the closure valve 19 is open and the bleed-off valve 21 is closed the injector transports via the suction pipe 5 an adjusted amount of a washing agent from the container 7 to the flow of fluid. The governing valve 10 is thereby closed and the fluid must therefore pass through the injector. Due to the reduced area of the injector, the pressure in conduit 16, 17 and in the jet pipe 20 will be lower than the pressure upstream of the injector 4.

If a shift over to high pressure shall be performed in order to start jet cleaning without washing agents, the closure valve 19 is momentarilly closed in order to bring about a pressure increase in the system downstream of the injector. Such an pressure increase urges the piston 12 to move against the action of the spring 14 and the valve member 11 is thereby opened. The fluid from the pump then can flow through the by-pass conduit 8, 9 and to the jet pipe 20 at the same high pressure. The pressure in the system is due to the com paratively small flow area of the jet nozzle 23 maintained at such a high level that the valve member 1 1 remains in its open position. If there shall be no supply of washing agent during the high pressure jet cleaning this is prevented by dimensioning the smallest crosssectional flow area of the injector somewhat smaller than the flow area of the jet nozzle 23.

In order to start the washing agent supply again the bleed-off valve 21 is opened during a short period of time whereupon the fluid is allowed to pass through said bleed-off valve which gives a much lower flow resistance than the jet nozzle 23. The pressure in the cyl inder 13 of the governing valve is thereby reduced and the valve member 11 closes. The fluid from the high pressure pump thereupon can pass only through the injector 4.

During the work it is necessary to be able now and then to interrupt the washing at low pressure without a subsequent high pressure jet cleaning. In order to prevent an undesirable shift over to high pressure jet cleaning at each of said interruptions there is fitted a check valve 22 to the bleed-off valve 21. The check valve is designed to open at a pressure just below the pressure upstream of the injector 4, but above the pressure prevailing at the downstream side of the injector when this operates normally, i.e. during washing agent supply. The bleed-off valve is thus kept at open position during the working period.

In P16. 2 there is shown a modified embodiment of the valve means 18 fitted in conduit 17 downstream of the injector. ln this embodiment the valve means is a single three-way valve having a turnable valve body which easily can be set in three different positions, i.e. a first one such as showed in the figure where the valve permits high pressure jet cleaning, a second one position where the valve member has been turned through 90 in clock-wise direction and in which position the conduit 17 is closed for bringing about a desired shiftover and finally a third position where the valve member has been turned through a further 90 in clockwise direction and in which third position low pressure washing is performed, the bleed-off effect being controlled by check valve 22. This valve means embodi- 1. In a washing and high pressure jet cleaning apparatus of the kind including a jet nozzle and an injector for the supply of a washing agent to the apparatus, the combination of a first conduit by-passing the said injector,

a first valve means fitted in said by-pass conduit,

a hydraulically operated governing means adapted to control the position of said first valve means,

means fitted adjacent to said governing means and biasing the said first valve means towards closed position,

a second conduit down-stream of said injector, said second conduit at its end remote from the injector being provided with said jet nozzle,

a third conduit connecting the said second conduit to the said governing means and intended to counteract the said biasing means in order to open said first valve means following a rise in pressure in said second conduit,

and further valve means fitted in the said second conduit and adapted for amending the pressure in said second conduit.

2. The apparatus as claimed in claim 1 wherein the second valve means includes a closure valve fitted in the said second conduit close by the jet nozzle said closure valve being adapted to bring about the rise in pressure, and a bleed-off valve fitted adjacent to the closure valve, said bleed-off valve being adapted to bring about a decrease in pressure sufficient to allow the said biasing means to close the said valve means.

3. The apparatus as claimed in claim -2 wherein a check valve is connected to said bleed-off valve, said check valve being designed to open at a pressure somewhat lower than the pressure upstream of the injector but higher than the pressure downstream of the injector during normal operation of the latter.

4. The apparatus as claimed in claim 1 wherein the smallest cross-sectional area of the injectoris smaller than the cross-sectional flow area of the jet nozzle.

32 3 UNITED STATES PATENT OFFICE CERTIFICATE 'OF CORRECTION Patent No. 3,829,024 Dated .August 13, 1974 Inventor(s) Olle Heden It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 4, "of" should read --comprising-;

line 5, delete "said";

line 7, delete "a", and "adapted to" should read for controlling--;

line 8, delete "control";

line 9, "and" should read for--;

line l0 delete "the", and insert theafter "towards";

line l5, delete "the";

line 16, delete "the";

line 17, delete "the";

line 23, "the" (second occurrence) should read said further-;

line 24, delete "second";

line 25, delete "the" (first occurrence), and insert after "nozzle"; j

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION pate t No, 3,829,024 Dated August 13, 1974 Inventofls) lle Heden Pag 2 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 27, insert -in said second conduit-- after "sure";

line 29, delete "the";

line 30, insert --first before "valve";

line 36, "latter" should read injector.

Signed and sealed this 3rd day of June 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks 

1. In a washing and high pressure jet cleaning apparatus of the kind including a jet nozzle and an injector for the supply of a washing agent to the apparatus, the combination of a first conduit by-passing the said injector, a first valve means fitted in said by-pass conduit, a hydraulically operated governing means adapted to control the position of said first valve means, means fitted adjacent to said governing means and biasing the said first valve means towards closed position, a second conduit down-stream of said injector, said second conduit at its end remote from the injector being provided with said jet nozzle, a third conduit connecting the said second conduit to the said governing means and intended to counteract the said biasing means in order to open said first valve means following a rise in pressure in said second conduit, and further valve means fitted in the said second conduit and adapted for amending the pressure in said second conduit.
 2. The apparatus as claimed in claim 1 wherein the second valve means includes a closure valve fitted in the said second conduit close by the jet nozzle said closure valve being adapted to bring about the rise in pressure, and a bleed-off valve fitted adjacent to the closure valve, said bleed-off valve being adapted to bring about a decrease in pressure sufficient to allow the said biasing means to close the said valve means.
 3. The apparatus as claimed in claim 2 wherein a check valve is connected to said bleed-off valve, said check valve being designed to open at a pressure somewhat lower than the pressure upstream of the injector but higher than the pressure downstream of the injector during normal operation of the latter.
 4. The apparatus as claimed in claim 1 wherein the smallest cross-sectional area of the injector is smaller than the cross-sectional flow area of the jet nozzle. 